Incandescent electric lamp



(No Model.)

I; J. FLAGG.

INGANDESUENT ELECTRIC LAMP.

Patented May 26,1891.

jwenzbowz UNITED STATES PATENT ()FFICE.

ISAAC J. FLAGG, OF CLINTON, MASSACHUSETTS.

INCANDESCENT ELECTRIC LAMP.

SPECIFICATION forming part of Letters Patent No. 452,780, dated May 26,1891.

Application filed $eptember 17, 1890. Serial No. 365,207, (No model.)

To aZZ whom it may concern.-

Be it known that I, ISAAC .I. FLAGG, of Olinton, county of lVorcester,State of Massachusetts, have invented an Improvement in IncandescentElectric Lamps, of which the following description, in connection withthe accompanying drawing, is a specification, like letters and figureson the drawing representing like parts.

In electric incandescent lamps as now commonly made the conducting wiresor terminals are led through plaster-of-paris or some equivalentmoisture-conducting substance, and such lamps cannot be used for anyc011- siderable time in dye -houses, bleacheries, and damp places, formoisture or dampness collecting in the said plaster-of-paris travelstherein and short-circuits the lamp, extinguishing the light. In myexperiments to obviate the trouble I have inclosed the conducting orterminal wires in a cablehaving an insulated sheath or covering, andwhere the conductors or terminals are laid bare within the socket of thelamp to enable them to be connected with the usual platinum wires incommunication with the usual carbon filament I have embedded the saidbared terminals and the platinum wires in a water andmoisture proofinsulating material.

To enable the weight of the lamp to be sustained by the insulated cableor suspensory I have applied some plaster-oE-paris or calcium plaster inthe socket about the suspen sory, but to protect the same from moisturethe upper end of the socket is filled in about the suspensory ontheinsulation thereof with a moisture and water proof material, so thatit is impossible for moisture to come in contact with the terminal wireswithin the socket of the lamp to short-circuit the carbon.

My invention consists in the comblnation, with the socket of the lampand its conducting wires or' terminals, of water and moisture proofinsulation to surround and protect the conducting-wires at their pointof contact with the usual platinum wires in communication with the usualcarbon filament, substantially as will be described.

The drawing represents in longitudinal section an incandescent electriclamp embodying my invention.

The lamp consists, essentially, of a bulb a,

and a socket Z) in one piece of glass or vitreous material.

My improved lamp may be made by fashioning the lamp between the lines a:00 of usual shape and material. The socket Z), also of glass or vitreousmaterial, hasa bottom or end piece 0 containing usual wires 2 2, withwhich is connected the usual carbon filament d. The closed end of thesocket, after platinum wires (with carbon attached) have been insertedin the closed end and the upper open end of the bulb, are byheat broughtinto a semifiuid or molten condition, or into such condition that whenput in contact they will weld or unite as one piece, the degree of heatto be applied for the purpose being well known to glass-blowers. Thesetwo parts a b, welded together at their points of contact 4, becomepractically one piece without leavinga space or seam, and it isimpossible for moisture to enter the lamp from outside the bulborsocket. The conductingwvires 5 5, laid bare below the insulation orcovering 6, are hooked into the platinum or other usual wires 2, withwhich are connected the opposite ends of the carbon d. The socket isthen filled with an insulating water and moisture proof C0111- pound, asatf, composed of tar or pitch of some usual kind, the said materialcovering the bared conducting-wires and preventing the passage ofmoisture from one to the other, which would short-circuit the carbon andput out the lamp. The upper end of the socket, outside the insulation 6,is filled or packed with a like tarry insulating and water and moistureproof compound, as 7L, which may be the same as that used about thebared wires. Between these insulating water and moisture proof compoundsf and h the socket has run into it plaster-of-paris or calcium plaster,as at 9, it being used because of the property it possesses of firmlyadhering to glass, it also holding firmly to the insulation e andsustaining the weight of the lamp. The insulating-wires or suspensoryisflexible and of any desired length, according to the spot where the lampis to be used.

Having described my invention, I claim 1. An incandescent lamp havingits bulb and socket in one piece of vitreous material and the insulatedsuspensory containing the conducting-wires, combined with terminals 2 2for the lamp and with which the said conducting-wires are joined withinthe socket, and water and moisture proof insulation, as f, surroundingthe said terminals and the bared conducting-wires at their point of junction within the said socket, substantially as described.

2. The combination, with the bulb of an incandescent lamp, its socketsecured thereto Inoisturetight, and the lamp-terminals extended into thesaid socket, of an insulated conductor to which the lamp is connectedWithin the socket, the wires of the conductor being connected tothelamp-terminals within the socket, and water and moisture proofinsulating material within the socket enveloping the lamp-terminals andthe conductors to which th ey are joined, whereby short-circuiting ofthe lamp at the junction of the terminals and the conductors isobviated, substantially as described.

3. The combination, with the lamp-socket, its terminals 2 2, and theinsulated suspeir sory having the conducting-wires, of the water-proofinsulation f, surrounding the conducting-wires below the point where theinsulation is removed therefrom to be joined with the terminals, and abinder g, surrounding the conductor within the socket to secure the lampto the suspensory, substantially as described.

4. The combination, with the lamp-socket, its wires 2, and the insulatedsuspensoryhaving the conducting-Wires, of the water-proof insulation fsurrounding the conductingwires below the point where the insulation isremoved, and the binding material 9 and the waterproof insulation aboveit in the said socket, substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ISAAC J. FLAGG.

Witnesses:

THOMAS J. Ksii'rixc, JEROME A. CRANE.

